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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | -1 |
| 3 | 2 |
| 4 | -5 |
| 5 | 14 |
| 6 | -35 |
| 7 | -14 |
| 8 | 1701 |
| 9 | -26418 |
| 10 | 351351 |
| 11 | -4622982 |
| 12 | 62705643 |
| 13 | -890078826 |
| 14 | 13297263525 |
| 15 | -209438953542 |
| 16 | 3477446002485 |
| 17 | -60803484275898 |
| 18 | 1117975706702127 |
| 19 | -21580455768575886 |
| 20 | 436591651807054107 |
| 21 | -9241512424454751714 |
| 22 | 204338436416329792941 |
[0,1,-1,2,-5,14,-35,-14,1701,-26418,351351, -4622982,62705643,-890078826,13297263525, -209438953542,3477446002485,-60803484275898, 1117975706702127,-21580455768575886, 436591651807054107,-9241512424454751714, 204338436416329792941] |